Print From Your Computer : Macintosh Printing (Mac OS X 10.4)

Select Page Options
Open the Page Setup window to select your page options.
Open the File menu and select Page Setup.
Select Artisan 720 as the Format for setting.
Select the Paper Size setting for the paper you loaded. Choose Manage Custom Sizes if you want to create a custom size.
If you want to print a borderless photo, select a Borderless paper size.
For borderless photos, make sure you loaded a compatible borderless paper size and type.
Choose a portrait or landscape Orientation option for your document or photo. (Choose  landscape left for envelopes.)
Click OK to close the Page Setup window.
Now you can select your print settings and print.